RJ11 wiring
The six-position telephone pinout, shown for one, two, and three lines. Covers both the old four-colour quad station wire and the twisted-pair equivalent used in modern work, explains tip and ring, and shows why lines number outward from the centre pair.
Six positions, three lines, two colour systems.
Two lines. Adds positions 2 and 5.
Cat5e or Cat6 — normal in anything installed this century.
Clip away from you, contacts toward you, position 1 on the left. Faded positions exist on the body but are not loaded on this variant.
- Line 1pins 3 & 4
- Line 2pins 2 & 5
- Line 3pins 1 & 6
This is why a single-line cord always finds line 1 whatever it is plugged into: line 1 sits on the centre pair, and every larger variant builds outward around it.
| Pin | Line | Side | Conductor |
|---|---|---|---|
| 1 | 3 | tip | white/green |
| 2 | 2 | tip | white/orange |
| 3 | 1 | tip | white/blue |
| 4 | 1 | ring | blue |
| 5 | 2 | ring | orange |
| 6 | 3 | ring | green |
Now do it
from memory
Six positions, and the only thing to remember is that lines build outward from the middle. Place the conductors and check.
Two lines. Adds positions 2 and 5.
Place the twisted-pair conductors for 6P4C. Lines work outward from the centre, so line 1 sits on the middle two positions.
Select a conductor, then the position it belongs in. Select a filled position to lift it back out. Nothing is timed until you start.
Doing it
Terminating a phone jack, and confirming you have the line you think you have before you close the wall.
- Punchdown tool or crimp tool for six-position plugs
- Toner and probe
- Station wire or Cat5e
- Six-position jacks or plugs
- 01
Establish which line you are working on
Lines work outward from the centre of the connector. Line 1 is positions 3 and 4, line 2 adds 2 and 5, line 3 adds 1 and 6. A single-line cord therefore always finds line 1 whatever it is plugged into.
- 02
Identify the cable you actually have
Older residential work uses four-colour quad — green, red, black, yellow. Anything installed recently uses twisted pair, where the blue pair is line 1 and the orange pair is line 2. The diagram above shows both.
CautionQuad wire is untwisted and unsuitable for data. Do not reuse a quad run for Ethernet.
- 03
Confirm the line is not ringing
A POTS line idles at about −48 V DC and rises to roughly 90 V AC while ringing. Take the handset off hook at the far end, or disconnect at the demarcation point, before handling bare conductors.
CautionRing voltage will not injure a healthy adult, but the reflex it triggers on a ladder can.
- 04
Terminate tip and ring the right way round
Tip is the white-striped conductor, ring is the solid. On most analogue equipment a reversal still works, which is precisely why the mistake spreads through a building unnoticed until something polarity-sensitive arrives.
- 05
Test with a butt set or a working handset
Dial tone at the jack confirms the pair and the polarity together. A continuity test alone will not tell you that you have line 2 on a line 1 jack.
- What is the difference between RJ11, RJ14 and RJ25?
- They share the same six-position body and differ only in how many contacts are loaded. RJ11 loads two contacts for one line, RJ14 loads four for two lines, and RJ25 loads all six for three lines.
- Can I plug an RJ11 cord into an RJ45 jack?
- It fits, but do not. The narrower plug can deform the outer contacts of the eight-position jack, and the damage is invisible until that jack is used for data and fails intermittently.
- Which wires are line 1 on a phone jack?
- The centre two positions — 3 and 4. On quad station wire that is green (tip) and red (ring); on twisted pair it is white/blue (tip) and blue (ring).
- Can I run a phone line over Cat5e?
- Yes, and it is the better practice. Use the blue pair for line 1 and the orange pair for line 2. A Cat5e run also leaves the option of repurposing the cable for data later, which quad wire does not.
The rest of the section
- 01RJ45 Wiring: T568A and T568BBoth colour codes, pin by pin, side by side.
- 02Keystone Jack TerminationStrip, seat, punch, snap — without failing the certification.
- 0366 Block WiringFifty rows, four columns, and where the bridging clips go.
- 04110 Block WiringLay the pairs in, press the connecting block on.
- 05Writing a Switch ConfigurationFrom factory default to a switch you would hand over.
- 06Networking and Cabling GlossaryThe terms, and what they mean on a job.
We do this work
as well as document it
Anyone terminating a phone jack, tracing a line in an older building, or working out why line 2 is dead.